Make the Black Bean & Corn burger mix: Heat the olive oil in a large skillet over medium heat. Once the oil begins to shimmer, add the onion and cook for 3-4 minutes, until semi-translucent. Add the garlic and carrots and cook for 2-3 minutes, until the carrots are partially tender.

Add the cumin, chili powder, coriander, cayenne, salt, pepper, and soy sauce. Cook for 2-3 minutes more, until the carrots are tender. Remove from the heat and set aside.

Add the black beans to a large bowl, and mash with a potato masher until mostly. Add the oats, corn, and carrot mixture and mix until well-combined.

Grease a large baking sheet with cooking spray. Using a spoon and your hands, shape the black bean burger mix into a quarter circle shape.

Make the Chickpea, Quinoa, & Sun-Dried Tomato burger mix: In a food processor, combine the chickpeas, quinoa, bread crumbs, sun-dried tomatoes, tahini, parsley, garlic, salt, pepper, oregano, and basil. Pulse until smooth. Shape the chickpea, quinoa burger mix into a quarter circle next to the black bean burger mix. Add to the baking sheet with the other burger mix.

Make the Sweet Potato & White Bean burger mix: In a large bowl, combine the white beans and sweet potato, and mash with a potato masher until smooth. Add the onion, bread crumbs, nutritional yeast, parsley, lemon juice, red chile flakes, garlic powder, salt, and pepper, and mix until well-combined. Add to the baking sheet with the other burger mixes.

Make the Mushroom Lentil burger mix: In a small bowl, combine the flax meal and water to make a flax egg. Set aside.

Heat 1 tablespoon of olive oil in a large pan over medium heat. Once the oil begins to shimmer, add the mushrooms and cook until most of the juices have evaporated, 7-8 minutes. Add the soy sauce and paprika and cook for 2-3 more minutes. Transfer to a large bowl and set aside.

Heat another tablespoon of olive oil in the pan over medium heat. Once the oil begins to shimmer, add the onion and cook for 3-5 minutes, until semi-translucent. Add the garlic and cook for 2 minutes, until fragrant. Add the salt and pepper, and cook for another 2 minutes.

Transfer the onion mixture to a food processor and add the lentils, oats, and flax egg. Pulse until a chunky paste forms.

Transfer the lentil mixture to the bowl with the mushrooms and mix until well-combined. Add to the baking sheet.

Preheat the oven to 350°F (180°C).

Shape the burger mixes to match the size of your loaf of bread. Press the borders together to create one cohesive patty.

Bake the patty for 20 minutes.

Make the special sauce: In a small bowl, combine the vegan mayo, ketchup, mustard, salt, and pepper, and stir until combined. Transfer to a squeeze bottle.

Remove the patty from the oven ,and top the Mushroom Lentil and Black Bean & Corn sections with the vegan provolone cheese.

Broil for 5 minutes, or until the cheese has melted.

With a large bread knife, slice the loaf of bread in half to make a giant bun.

With large spatulas or bench scrapers, transfer the veggie burger patty onto the bottom half of the bun.

Spread the avocado crema on top of the the Chickpea Quinoa, Sweet Potato & White Bean sections. Squeeze the special sauce onto the Black Bean & Corn and mushroom Lentil sections.

Layer on the lettuce, tomatoes, and red onion, and top with the top bun.